Perilipin 2-positive mononuclear phagocytes accumulate in the diabetic retina and promote PPARγ-dependent vasodegeneration.

Type 2 diabetes mellitus (T2DM), characterized by hyperglycemia and dyslipidemia, leads to nonproliferative diabetic retinopathy (NPDR). NPDR is associated with blood-retina barrier disruption, plasma exudates, microvascular degeneration, elevated inflammatory cytokine levels, and monocyte (Mo) infiltration. Whether and how the diabetes-associated changes in plasma lipid and carbohydrate levels modify Mo differentiation remains unknown. Here, we show that mononuclear phagocytes (MPs) in areas of vascular leakage in DR donor retinas expressed perilipin 2 (PLIN2), a marker of intracellular lipid load. Strong upregulation of PLIN2 was also observed when healthy donor Mos were treated with plasma from patients with T2DM or with palmitate concentrations typical of those found in T2DM plasma, but not under high-glucose conditions. PLIN2 expression correlated with the expression of other key genes involved in lipid metabolism (ACADVL, PDK4) and the DR biomarkers ANGPTL4 and CXCL8. Mechanistically, we show that lipid-exposed MPs induced capillary degeneration in ex vivo explants that was inhibited by pharmaceutical inhibition of PPARγ signaling. Our study reveals a mechanism linking dyslipidemia-induced MP polarization to the increased inflammatory cytokine levels and microvascular degeneration that characterize NPDR. This study provides comprehensive insights into the glycemia-independent activation of Mos in T2DM and identifies MP PPARγ as a target for inhibition of lipid-activated MPs in DR.

Discapacidad visual asociada a retinopatía diabética y edema macular: un estudio de base hospitalaria / Visual impairment associated with diabetic retinopathy and macular edema: a hospital-based study

Resumen Antecedentes: Los datos sobre discapacidad visual (DV) en pacientes con diabetes son necesarios para orientar los recursos económicos y humanos que disminuyan su prevalencia. Objetivo: Estimar la prevalencia de DV relacionada con retinopatía diabética en pacientes con diabetes tipo 2 en un entorno hospitalario. Material y métodos: Estudio transversal realizado de 2014 a 2019 en una consulta externa de oftalmología. Cualquier DV se definió como agudeza visual corregida con agujero estenopeico en el ojo con mejor visión (≥ 0.24 logMAR). Se evaluó la presencia de retinopatía diabética, edema macular diabético (EMD) y cataratas. Resultados: Se incluyeron 840 pacientes; la mediana de duración de la diabetes fue de 15 años. La prevalencia de DV fue de 30 %. Se encontró retinopatía diabética en 62 % (30 % tenía retinopatía diabética que amenazaba la visión [RDAV]); 17 %, EMD y 3 %, cataratas. La razón de momios para DV moderada o de mayor gravedad fue de 9.02 para RDAV (p < 0.001), 5.89 para EMD referible (p = 0.001) y 2.51 para catarata (p = 0.006). Conclusión: Treinta por ciento de los participantes tenía algún grado de DV. La DV moderada o de mayor gravedad mostró una fuerte asociación con RDAV y EMD referible.

Abstract Background: Data on visual impairment (VI) in patients with diabetes are necessary in order to guide economic and human resources for reducing its prevalence. Objective: To estimate the prevalence of diabetic retinopathy-related VI in patients with type 2 diabetes in a hospital-based setting. Material and methods: Cross-sectional study carried out from 2014 to 2019 in an ophthalmology outpatient clinic. Any VI was defined as corrected pin-hole visual acuity in the better eye of ≥ 0.24 logMAR. The presence of diabetic retinopathy (DR), diabetic macular edema (DME) and cataract was evaluated. Results: A total of 840 patients were included; median diabetes duration was 15 years. The prevalence of VI was 30 %. DR was found in 62 % of patients (30 % had sight-threatening DR [STDR]), 17 % had referable DME, and 3 %, cataracts. The odds ratio for moderate or worse VI was 9.02 for STDR (p < 0.001), 5.89 for referable DME (p = 0.001), and 2.51 for cataract (p = 0.006). Conclusion: Thirty percent of participants had some degree of VI. Moderate or worse VI showed a strong association with STDR and referable DME.

CHEMOTHERAPEUTIC NADIR-ASSOCIATED RETINOPATHY.

PURPOSE: To describe subinternal limiting membrane hemorrhage as a retinal complication of chemotherapy nadir in a patient with leukemia. METHODS: Case report. RESULTS: A 23-year-old man presented with bilateral subinternal limiting membrane hemorrhages in both eyes as a manifestation of thrombocytopenia secondary to chemotherapy treatment for acute myeloid leukemia. CONCLUSION: Chemotherapeutic nadir-associated retinopathy may present with sub-internal limiting membrane hemorrhages most probably secondary to thrombocytopenia.

MULTICOLOR SCANNING LASER IMAGING IN LIPEMIA RETINALIS.

PURPOSE: To describe multicolor scanning laser imaging (MSLI) and conventional fundus photography findings in lipemia retinalis (LR). METHODS: We report two LR cases. The first case is a 47-year-old diabetic woman with LR secondary to familial hypertriglyceridemia examined with MSLI, conventional fundus photography, and optical coherence tomography (OCT). The second case is a 39-year-old diabetic man with hypertriglyceridemia and LR. He was followed over time with conventional fundus photography of his retina until metabolic control was achieved. RESULTS: In the first case, MSLI showed retinal arteries with an intense yellow and retinal veins with a pale yellow color. Fundus photography disclosed only mild pale red vessels. Optical coherence tomography detected macular edema and hyperreflective changes of retinal vessels. In the second case, fundus photography showed vessels with a pale red appearance that normalized after metabolic control of triglycerides. CONCLUSION: We described the retinal findings in patients with LR using different image modalities. Specifically, we report the findings with MSLI not previously described. While regular fundus photography may show mild changes in LR, the MSLI modality may show more significant findings assisting in the diagnosis and follow-up of this disease.